Am Dienstag, 6. März 2018, 19:15:18 CET schrieb Marc Zyngier: > Hi Doug, > > On 06/03/18 18:00, Doug Anderson wrote: > > Hi, > > > > On Tue, Mar 6, 2018 at 3:58 AM, Marc Zyngier <marc.zyngier@xxxxxxx> wrote: > >> Hi all, > >> > >> On 01/03/18 08:43, Heiko Stübner wrote: > >>> Am Dienstag, 27. Februar 2018, 21:47:11 CET schrieb Douglas Anderson: > >>>> Back in the early days when gru devices were still under development > >>>> we found an issue where the WiFi reset line needed to be configured as > >>>> early as possible during the boot process to avoid the WiFi module > >>>> being in a bad state. > >>>> > >>>> We found that the way to get the kernel to do this in the earliest > >>>> possible place was to configure this line in the pinctrl hogs, so > >>>> that's what we did. For some history here you can see > >>>> <http://crosreview.com/368770>. After the time that change landed in > >>>> the kernel, we landed a firmware change to configure this line even > >>>> earlier. See <http://crosreview.com/399919>. However, even after the > >>>> firmware change landed we kept the kernel change to deal with the fact > >>>> that some people working on devices might take a little while to > >>>> update their firmware. > >>>> > >>>> At this there are definitely zero devices out in the wild that have > >>>> firmware without the fix in it. Specifically looking in the firmware > >>>> branch several critically important fixes for memory stability landed > >>>> after the patch in coreboot and I know we didn't ship without those. > >>>> Thus, by now, everyone should have the new firmware and it's safe to > >>>> not have the kernel set this up in a pinctrl hog. > >>>> > >>>> Historically, even though it wasn't needed to have this in a pinctrl > >>>> hog, we still kept it since it didn't hurt. Pinctrl would apply the > >>>> default hog at bootup and then would never touch things again. That > >>>> all changed with commit 981ed1bfbc6c ("pinctrl: Really force states > >>>> during suspend/resume"). After that commit then we'll re-apply the > >>>> default hog at resume time and that can screw up the reset state of > >>>> WiFi. ...and on rk3399 if you touch a device on PCIe in the wrong way > >>>> then the whole system can go haywire. That's what was happening. > >>>> Specifically you'd resume a rk3399-gru-* device and it would mostly > >>>> resume, then would crash with some crazy weird crash. > >>>> > >>>> One could say, perhaps, that the recent pinctrl change was at fault > >>>> (and should be fixed) since it changed behavior. ...but that's not > >>>> really true. The device tree for rk3399-gru is really to blame. > >>>> Specifically since the pinctrl is defined in the hog and not in the > >>>> "wlan-pd-n" node then the actual user of this pin doesn't have a > >>>> pinctrl entry for it. That's bad. > >>>> > >>>> Let's fix our problems by just moving the control of > >>>> "wlan_module_reset_l pinctrl" out of the hog and put them in the > >>>> proper place. > >>>> > >>>> NOTE: in theory, I think it should actually be possible to have a pin > >>>> controlled _both_ by the hog and by an actual device. Once the device > >>>> claims the pin I think the hog is supposed to let go. I'm not 100% > >>>> sure that this works and in any case this solution would be more > >>>> complex than is necessary. > >>>> > >>>> Reported-by: Marc Zyngier <marc.zyngier@xxxxxxx> > >>>> Fixes: 48f4d9796d99 ("arm64: dts: rockchip: add Gru/Kevin DTS") > >>>> Fixes: 981ed1bfbc6c ("pinctrl: Really force states during > >>>> suspend/resume") > >>>> Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx> > >>> > >>> applied as fix for 4.16 with the 2 Tested-tags > >> > >> Sorry to rain on everyone's parade, but further testing shows that this > >> patch may not be enough to restore a reliable s2r. My initial testing > >> did show that we were resuming without the VOP errors, but there seem to > >> be further issues (I'm loosing the keyboard and the trackpad after > >> resume on Kevin). > >> > >> Applying my initial hack makes it work again. I suspect that there are > >> more hog pins that need tweaking, but I'm a bit out of my depth here. > > > > Are you positive you weren't just wearing your lucky hat when you > > tested your patch and then took it off when you tested mine? As far > > So far, I seem to have a 100% success rate in resuming with my silly > hack, whist your DT patch alone only gives me a 50% rate at best. > > > as I can see the only hogs left on kevin are: > > &ap_pwroff /* AP will auto-assert this when in S3 */ > > &clk_32k /* This pin is always 32k on gru boards */ > > > > Those map to: > > ap_pwroff: ap-pwroff { > > > > rockchip,pins = <1 5 RK_FUNC_1 &pcfg_pull_none>; > > > > }; > > > > clk_32k: clk-32k { > > > > rockchip,pins = <0 0 RK_FUNC_2 &pcfg_pull_none>; > > > > }; > > > > So I added some printouts at suspend/resume time. Specifically I set > > a boolean to "true" for the duration rockchip_pinctrl_suspend() and > > rockchip_pinctrl_resume() and this turned on a printout in > > rockchip_set_mux(). My printout looked like this (yeah, I know it's a > > whitespace-damaged patch just to show what I'm doing): > > > > + regmap_read(regmap, reg, &before); > > > > data = (mask << (bit + 16)); > > rmask = data | (data >> 16); > > data |= (mux & mask) << bit; > > ret = regmap_update_bits(regmap, reg, rmask, data); > > > > + regmap_read(regmap, reg, &after); > > + > > + if (DOUG) { > > + dev_info(info->dev, > > + "setting mux of GPIO%d-%d to %d; > > %#010x=>%#010x\n", + bank->bank_num, pin, mux, > > reg, before, after); + } > > > > ...and a similar one in rockchip_set_pull(). That showed this at resume > > time: > > > > [ 62.284427] rockchip-pinctrl pinctrl: setting mux of GPIO1-5 to 1; > > 0x00009400=>0x00009400 > > [ 62.294423] rockchip-pinctrl pinctrl: setting pull of GPIO1-5; > > 0x000041aa=>0x000041aa > > [ 62.303343] rockchip-pinctrl pinctrl: setting mux of GPIO0-0 to 2; > > 0x00005002=>0x00005002 > > [ 62.313240] rockchip-pinctrl pinctrl: setting pull of GPIO0-0; > > 0x00000ddc=>0x00000ddc > > [ > > > > Said another way: pinmux and pull isn't actually changing due to the > > hogs. We can see if something else could be changing, but I'd really > > want to be sure you're certain that the hogs are causing you > > problems... > > I cannot say for sure that the hogs are the issue. But I thought that > they were the only pins affected by 981ed1bfbc6c... If this patch can > affect other pins, then I'm probably barking up the wrong tree. On Kevin I see something like [ 60.764129] cros-ec-spi spi2.0: spi transfer failed: -108 [ 60.764132] cros-ec-spi spi2.0: cs-deassert spi transfer failed: -108 [ 60.764136] cros-ec-spi spi2.0: Command xfer error (err:-108) [ 60.764365] cros-ec-spi spi2.0: spi transfer failed: -108 [ 60.764368] cros-ec-spi spi2.0: cs-deassert spi transfer failed: -108 [ 60.764371] cros-ec-spi spi2.0: Command xfer error (err:-108) on resume with my current for-next. So maybe your hack just happened to change some timing during resume? Suspend/Resume also disconnects my usb-ethernet, making me lose my nfsroot, so I can test this once every boot only. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
